Today, Pakistan became the first nation in South Asia to adopt daylight-saving time, pushing clocks forward by one hour. The three-month experiment is designed, as elsewhere, to cut energy costs by taking advantage of long summer days.

But what might make practical sense for Pakistan is yet another headache for a region that already clocks up more than its share of chronological confusion. For residents of South Asia, simply figuring out what time it is in the next country, let alone beyond that, can be an exercise in frustration.

Consider Pakistan lies west of India and is usually a half hour (yes, a half hour) behind its political archrival. But by winding its clocks forward Saturday, Pakistan is now a half hour ahead of India, whose time remains unchanged. The situation seems a little absurd, such as California being ahead of Nevada.

Or take India and its little neighbor Bangladesh. Imagine India as a friendly country with its arm slung over Bangladesh”s shoulder. The hand on the shoulder is India”s northeast corner, a sizable chunk of territory connected to the rest of India by a thin arm of land.

A Bangladeshi who crosses his country”s western border finds himself in India, whose time is set a half hour behind Bangladesh. So far, so good. But if he goes in the opposite direction, across the eastern frontier, he finds himself in India again, and still has to turn his watch back 30 minutes, even though the sun will rise earlier than it did when he was at home.

Maybe this feels too much like the movie “Groundhog Day.” To escape the time warp, you flee to Nepal, home of Mount Everest, scruffy backpackers and an easygoing spirituality.

Its time zone is different from any other country in South Asia — indeed, any other country on Earth — in an attempt, perhaps, to assert Nepal”s individuality.

Official time as decreed by Katmandu, the Nepalese capital, falls on the 15- or 45-minute mark relative to much of the rest of the world.

So when it”s 6 p.m. in New Delhi, it”s 6:15 p.m. in Katmandu. A worried mother in Los Angeles calling Nepal at 7:30 p.m., Pacific Daylight Time, will reach her mountain-trekking daughter just as the young woman is sitting down to a cup of butter tea for breakfast at 8:15 a.m. the next morning.

After the daughter scales Everest at 1 p.m., snaps a photo and starts climbing down the Chinese side of the mountain, she”ll find that she”s suddenly lost two and a half hours for her descent, because according to China, it”s already 3:15 p.m.

The head-spinning clutch of time zones in this region attests to the fact that a country”s official time is due as much, if not more, to political considerations as scientific ones.

For years, the island nation of Sri Lanka, off India”s southern tip, operated according to the same time as India: 5 1/2 hours ahead of Greenwich Mean Time, or GMT plus 5 1/2. To save energy, the Sri Lankan government decided in 1996 to nudge ahead its official time and, after a bit of experimentation, eventually settled on half an hour later, or GMT plus 6.

Buddhist astrologers warned that the change would bring bad luck. And Tamil Tiger rebels, who controlled the north and east of the island, refused to switch.

“Then the Sri Lankan military decided to operate on the same time as the insurgents. So you had half of the government and the rest of the country on a different time zone,” said Dilip Ahuja, a professor at the National Institute of Advanced Studies in the southern Indian city of Bangalore. “It was so confusing that they just gave up and went back to five and one-half hours.”

Ahuja knows so much about time zones because he and two co-authors published a paper in 2007 recommending that India adjust its own official time to GMT plus 6.

By shifting ahead half an hour, the country could shave at least 0.3 percent off its annual electricity consumption, a savings of $250 million, the study said.

Other potential benefits include fewer car accidents (India suffers more traffic fatalities and injuries “than entire continents,” the study noted), less street crime and the virtue of being in sync “on the hour” with 95 percent of the world, instead of on the half-hour.

Ahuja and his co-authors rule out splitting India into two time zones for east and west, although the country is big enough to accommodate it.

China insists on a single fixed time for the entire nation, despite spanning several potential time zones, for the sake of national unity, and India should stick to the same principle, Ahuja said.

It”s just that he hopes the Indian government will, out of simple pragmatism, take up his suggestion to shift everyone”s clock to half an hour later.